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31.
Michael H. Erhard Reiner Kühlmann Ladislaus Szinicz Uli Lösch 《Archives of toxicology》1990,64(7):580-585
The development of a specific and sensitive immunologic ELISA detection system for methylphosphonoflouridic acid. 1,2,2-trimethylpropylester (soman) by the use of monoclonal antibodies (MAbs) is described. The monoclonal antibodies F71D7, F71H10, F71B12 and F71H9 originally produced against the soman derivative methyl phosphonic acid,p-aminophenyl 1,2,2-trimethylpropyldiester (MATP) also reacted with soman in a previously developed, direct competitive ELISA. After optimizing the ELISA system by varying the reaction mixture and the solvents for the organophosphate, 5.0×10–7 mol/l soman (80% purity), e.g. 2.5 ng or 2 ng pure soman per 25 l test buffer, could be detected after a total test duration of 40 min. A shortening of the incubation time to 10 min resulted in a drop of sensitivity to 1.8×10–6 mol/l soman. Various alcohols which may be used as extraction media for soman from various materials (isopropanol, ethanol and methanol) were shown to inhibit peroxidase activity and thereby reduce the sensitivity of the test. However, the influence of alcohols decreased with the shortening of incubation time. All monoclonal antibodies showed little cross reactivity to sarin and no cross reactivity to tabun and VX. Judging on the reactivity of the MAbs with MATP and soman oxidazed by 1,2-dihydrobenzol, some reactivity with some other (non-toxic) soman analogues containing the same pinacolyl group can be expected. There was no evidence for stereoselectivity of the MAbs tested. Finally, soman could be detected in different biological samples like human serum, goat serum, rabbit serum, chicken serum, milk, and tap water in concentrations between 1.3×10–6 and 2.0×10–6 mol/l. 相似文献
32.
四乙基胺抑制蟾酥的强心效应 总被引:1,自引:0,他引:1
[目的]观察蟾酥对离体蟾蜍心脏收缩运动的影响和各种受体阻断剂、钾通道阻断剂对这种效应的影响。[方法]将离体蟾蜍心脏收缩运动用张力换能器转换成电信号,通过Doctor-95 Super Lab软件系统在电脑上连续记录心率和收缩力的变化,并打印成曲线。[结果]取自蟾蜍同体耳后腺的蟾酥对离体蟾蜍心脏收缩运动有增强作用。M受体阻断剂阿托品(0.5g/L)和β受体阻断剂心得安(0.01g/L)不能阻断蟾酥对离体蟾蜍心脏收缩运动的增强作用,而α受体阻断剂酚妥拉明(0.5g/L)、非选择性钾通道阻断剂四乙基胺(10mmol/L)则明显抑制蟾酥对离体蟾蜍心脏收缩运动的增强作用。[结论]蟾酥是通过α受体作用于钾通道而增强离体蟾蜍心脏收缩运动。 相似文献
33.
目的:对比研究胰岛素加磺脲类药联合(INS/SU)或单用胰岛素(INS)二种疗法治疗继发性SU失效的疗效,并通过体外试验探讨INS加SU治疗的机理。方法:54例继发SU失效的2型糖尿病患者随机分二组,分别给INS加SU及INS治疗共3个月,测定2型糖尿病患者脂肪细胞与优降糖孵育后INS受体结合位点。结果:(1)治疗3个月时两组的血糖、糖化血红蛋白(HbAIc)得到较好控制。(2)两组治疗前后血脂无明显改变。(3)INS组较INS加SU组体重增加显著、血INS水平明显升高。(4)优降糖孵育后的脂肪细胞INS结合位点增多,与INS特异结合率提高。结论:(1)INS加SU与INS均可有效地治疗继发性SU失效的病人。(2)INS加SU联合治疗与单用INS治疗比较,其引起的血INS水平升高、体重增加程度均较低。(3)SU通过影响靶细胞INS受体等胰外作用.而增强INS的作用效应。 相似文献
34.
我们收集 1 990~ 1 999年共 5 0 0例临床确诊为椎 基底动脉供血不足 (Vertebrobasilarinsufficiency ,VBI)的中老年病人 ,采用经颅多普勒超声 (TCD)检测对该病病因进行探讨 ,结果报告如下。1 资料与方法 5 0 0例受检者中男性 2 85例 ,女性 2 1 5例 ,平均年龄 5 6 .4岁。病程 8d至 2 0年 ,均以发作性眩晕起病。主要表现为反复发作性眩晕、头昏、呕吐、耳鸣、听力减退、视物模糊、四肢麻木、共济失调等症状。其它检查发现该组病例具有颈椎病、高血压、脑动脉粥样硬化症、高脂血症、高粘血症等。以… 相似文献
35.
中药灯盏细辛化学成分的研究(Ⅱ) 总被引:15,自引:0,他引:15
目的:进一步研究灯盏细辛「Erigeron breviscapus(Vant.)Hand.-Mazz.」的化学成分。方法:采用硅胶柱层析对灯盏细辛的氯仿萃取部分的化学成分进行分离和纯化,应用理化常数和光谱分析(IR,MS,^1HNMR,^13CNMR)鉴定其结构。结果:得到6个单体化合物,结构分别为3,4-二羟基肉桂酸(3,4-dihydroxy-phenyl acrylic acid,Ⅶ),α-甲氧基-γ-吡喃酮(α-methoxy-γ-pyranone,Ⅷ)、豆甾醇(stigmasterol,Ⅺ)、胡萝卜甙(β-sistosterol-3-O-β-D-glucopyranoside,Ⅻ)。结论:化合物Ⅶ,Ⅷ,Ⅺ,Ⅻ为首次从本植物中分得。 相似文献
36.
37.
- The actions of several neuroleptic and tricyclic compounds were examined on the large conductance Ca2+-activated K+ (BKCa) channel present in neurones isolated from the rat motor cortex.
- Classical neuroleptic compounds including chlorpromazine and haloperidol applied to the intracellular surface of inside-out patches produced a concentration-dependent reduction in BKCa channel activity. Similar effects were observed when these compounds were applied to the extracellular surface of outside-out patches.
- In contrast, the atypical neuroleptic compounds clozapine and sulpiride did not affect BKCa channel activity (100 nM–1 mM) in either inside-out or outside-out patches, while 10 μM pimozide produced 73% of the inhibition produced by 10 μM chlorpromazine.
- BKCa channel activity was also unaffected by application of structurally related tricyclic compounds including the anti-cholinesterase tacrine and the anti-epileptic carbamazepine. The tricyclic antidepressant drug amitriptyline was found to inhibit BKCa channel activity but was much less effective than the classical neuroleptic compounds.
- It is concluded that compounds belonging to the classical neuroleptic group of drugs inhibit BKCa channel activity in the rat motor cortex in a structurally-specific manner. This observation may be of clinical significance as it may contribute to some of the side effects associated with classical neuroleptic drug therapy.
38.
颈动脉系统TIA脑血液动力学的研究 总被引:1,自引:0,他引:1
目的:探讨短暂性脑缺血发作(TIA)的发病机制。方法:对30例劲动脉系统TIA进行三维经颅多普勒超声(3D-TCD)、脑血管血液动力学参数(CVDI)及血液流变学检查分析。结果:绝大我数患者存在严重脑动脉硬化、脑动脉狭窄、脑内循环障碍;病灶侧平均脑血流量下降,血管自身调节功能减退;全血粘度、血浆粘度及血小板聚集率明显增高。结论:脑血液动力学障碍是TIA发病机制之一。 相似文献
39.
Benign and malignant hepatocellular tumors: evaluation of tumoral enhancement after mangafodipir trisodium injection on MR imaging 总被引:2,自引:0,他引:2
Coffin CM Diche T Mahfouz A Alexandre M Caseiro-Alves F Rahmouni A Vasile N Mathieu D 《European radiology》1999,9(3):444-449
The aim of this work was to study the ability of mangafodipir trisodium (Mn-DPDP)-enhanced MR imaging in differentiating
malignant from benign hepatocellular tumors. Eleven patients with pathologically proved hepatocellular carcinomas, six with
focal nodular hyperplasias, and one with a single hepatocellular adenoma were examined by spin-echo and gradient-echo T1-weighted
sequences before, 1 h after, and 24 h after intravenous injection of Mn-DPDP (5 μmol/kg). Quantitative analysis including
enhancement and lesion-to-liver contrast-to-noise ratio, and qualitative analysis including the presence of a central area
and a capsule were done on pre- and post-Mn-DPDP-enhanced images. Enhancement was observed in all the tumors with significant
improvement (p < 0.05) in contrast-to-noise ratio 1 h after, and 24 h after intravenous injection of Mn-DPDP. There were no significant
differences in the mean enhancement and the mean contrast-to-noise ratio (CNR) between benign and malignant tumors. No enhancement
was seen within internal areas observed in 7 hepatocellular carcinomas, and in 5 focal nodular hyperplasias, and within capsules
which were observed in 9 hepatocellular carcinomas. In our study, Mn-DPDP increased CNR of both benign and malignant tumors
but did not enable differentiation between benign and malignant tumors of hepatocellular nature.
Received: 7 October 1997; Revision received: 25 February 1998; Accepted: 10 July 1998 相似文献
40.
重组人神经营养因子-4/5蛋白抗三氧化二砷神经毒作用 总被引:5,自引:0,他引:5
目的初步观察重组人神经营养因子-4/5(hNT-4/5)蛋白对三氧化二砷毒性的抑制作用。方法利用hNT-4/5蛋白具有抗神经毒性的特点,采用本实验室克隆表达及部分纯化的具有天然hNT-4/5蛋白生物学活性的重组hNT-4/5蛋白,以不同水平的重组hNT4/5蛋白(0-100μl)与不同浓度的As2O3(0-160μmol/L)同时加入各组鸡胚前脑神经细胞和PC12细胞培养液中共同孵育24-48小时,观察其对染毒鸡胚前脑神经细胞存活和PC12细胞突起生长的影响作用。结果在鸡胚前脑神经细胞和PC12细胞中与As2O3共同培养48小时后,对照组与实验组的细胞存活率差异有显著性,而且细胞存活率和突起数目随hNT-4/5浓度增高而提高和增加。结论初步观察到重组hNT4/5蛋白具有抑制As2O3的毒性作用,为从基因工程途径寻找抗环境毒物因子提供了依据。 相似文献